Data buses are made redundant to improve reliability: if one side, or bus, fails, the other can continue to operate. Primary and redundant data buses are typically synchronized to a single clock, or timing server, to enable simultaneous operation and rapid switchover in the event of a failure. While the data bus may quickly adapt to the failure of ordinary nodes, the failure of the timing server continues to present challenges to those seeking seamless redundancy. Existing methods use multiple timing servers having a master timing server and one or more redundant timing servers. In the event the master timing server fails, the remaining timing servers interactively negotiate by exchanging signals unique to the purpose of negotiation to determine which of the remaining timing servers will become the master. Operation of the data bus may be suspended during interactive negotiations, and data may be undesirably delayed.
Accordingly, it is desirable to have a seamless technique for responding to the loss of a master timing server, whether from failure of the master timing server itself or failure of the portion of the data bus coupled to the master timing server. In addition, it is desirable to have a selection protocol which obviates delays for interactive negotiations. It is also desirable to have a data bus with a seamlessly fail-operational global time reference. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.